


lights out then lock-up

by screechfox



Series: they keep trying to row away [1]
Category: The Magnus Archives (Podcast)
Genre: Abuse, Additional Warnings in Author's Notes, Alternate Universe - Canon Divergence, Captivity, Dark, Dehumanization, Gen, MerMay, Monsters, Non-Consensual Body Modification, Starvation, Transformation, twisted caretaking
Language: English
Status: Completed
Published: 2020-05-07
Updated: 2020-06-21
Packaged: 2021-03-02 20:09:13
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 4
Words: 8,567
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24062647
Author URL: https://archiveofourown.org/users/screechfox/pseuds/screechfox
Summary: It starts with suffocation.Or; Jon finds himself slowly transforming into something else. Elias helps, for want of a better word.
Relationships: Elias Bouchard & Jonathan Sims
Series: they keep trying to row away [1]
Series URL: https://archiveofourown.org/series/1735714
Comments: 121
Kudos: 356
Collections: RaeLynn's Epic Rec List





	1. suffocation

**Author's Note:**

> sometimes an idea just overtakes you. sometimes you get to write the weird mermaid-based body horror you've been dreaming of since you read that one really weird emily windsnap book as a kid, except even worse. title paraphrased by all the rowboats by regina spektor.
> 
> thanks to the server for encouragement and brainstorming and especial thanks to the collaborators on this series, which you should absolutely go and read the rest of, while minding the warnings!

**Notes for the Chapter:**

> chapter-specific warnings in chapter end notes

It starts with suffocation.

Well, more accurately, it starts with thin lines on either side of Jon’s neck, red and sensitive. Over the course of a few days, he takes to wearing shirts with low necklines to try and prevent irritation, but it only gets worse, until he feels like his skin is going to split underneath his fingertips. 

One moment, he can breathe just fine; the next, every inhale is like acid in his throat.

The other researchers shoot him worried looks as he stands up. No amount of hyperventilation brings relief to his lungs. He stammers something, he’s not sure what — he needs some fresh air, or something to drink, or a throat lozenge — and then flees the office.

He’s so deprived of oxygen, he can’t make himself focus on any one solution. Does he head for the front door of the Institute, or the break-room with its glasses of water and first aid kit? Is he having an allergic reaction, perhaps? He can’t think what he’d be reacting to— but then, he can hardly think at all, animal panic clawing at what’s left of his coherent thoughts.

When he runs into Elias, Jon is half-convinced he’s going to die here and not even know why.

Elias looks calm, if mildly concerned about the way Jon trips into him. He presses his hands to Jon’s cheeks, guiding his head this way and that as if in examination. Elias’ hands are so warm — or is Jon the one who’s cold, skin turned bloodless and clammy as he chokes to death with nothing to show for himself? Elias hums, as though confirming something he’d long-suspected.

“Come with me.”

It isn’t as though Jon has the strength to resist. All he can do is let Elias support his weight, ushering him upstairs slowly but surely. He stumbles on the last stair as his vision begins to blur.

“Steady, Jon,” he hears Elias murmur, as though from very far away. “Just a few steps more.”

One hand on his back, Elias guides Jon into his office, into another room to the side. Before he can react, Elias pulls him off his feet, depositing him without ceremony in a bath of freezing cold water and forcing his head below the surface. Jon’s struggles are to no avail. Elias’ calm is marred by the faintest hints of displeasure as water splashes across his skin, but he’s as unyielding as marble. It’s only now, as he holds Jon below the water, that Jon notices that Elias’ shirt-sleeves are rolled up.

“Steady,” Elias says again, sharper this time. “Just relax for me, Jon.”

The need to survive is strong, but Jon forces himself to go still. He reasons — startled by the coherency of his thoughts — that he was suffocating even before Elias tried to drown him.

Elias’ thumbs brush gently across Jon’s upper arms, and Jon feels a strange calm overtake him. Is this what drowning feels like? Like you’re becoming one with the water around you, temperatures equalising; like air in your lungs is a long-forgotten notion, a daydream?

“There you go,” Elias murmurs, his voice distorted in the slow shift of the water.

Maybe dying feels like coming home, or maybe— maybe Jon can breathe again.

He gets enough leverage to press his fingers to the lines on his neck, feeling the way they rise and fall. They don’t hurt anymore; these gashes feel as natural as if he were born with them. 

No, not gashes — gills. He has gills.

Jon is so distracted by this change in his body that he has no time to react when Elias slides a sheet of plexiglass over the top of the tub and fastens it in place with a hollow click. It doesn’t move when Jon presses his hands to it, nor when he kicks out at it with all of his strength.

“I’m very sorry,” Elias says, his voice barely audible in Jon’s confinement. He doesn’t look anything close to apologetic, just… quietly satisfied. “I have to get back to work, and I don’t want to risk you accidentally suffocating yourself because I wasn’t here to supervise you.”

Elias walks to the end of the bath and turns one of the taps. Hot water rushes in, mingling with the chill and stealing any last hint of air. Jon can’t pretend he’s not thankful for the warmth, but he’d be rather more thankful if he weren’t trapped in a space barely big enough for his body.

“It’s a good thing that this happened near the end of the day,” Elias continues, though it seems to be more for his own benefit. “It would be unpleasant to be stuck here for hours.”

With that, Elias leaves, the door locking behind him with a click.

Time quickly fades into a meaningless concept. 

Jon can pass five minutes thinking about the case he was looking into this morning, another five wondering what the other researchers thought about his sudden disappearance, and then his mind plummets into an abyss of questions he doesn’t have the answers to.

Why is this happening to him? Why did Elias have this bath prepared for him? How much time does he have before the water has too little oxygen to breathe? Why is Elias so _calm?_

Jon digs his nails into the gashes on his neck like he can split them open further until they bleed. It hurts. He hadn’t expected it to, as though the sensation would have been as alien as the gills.

It turns out that he can still hyperventilate. His panic makes waves in the water around him.

By the time Elias returns, Jon is light-headed; a mixture of physiological terror and inadequate oxygen in the water. He has no idea how long it’s been, but the meagre daylight that had been pouring through the bathroom window has long-since vanished into the dark of night.

“Apologies for the delay,” Elias says as he enters Jon’s field of vision. ”I was retrieving something from Artifact Storage that I thought might be helpful, and Sonja cajoled me into conversation.”

Jon has barely enough energy to tap his fingers on the covering above him, the harsh sound echoing in the water and making him flinch. If Elias leaves him trapped any longer, he may start screaming.

The look Elias gives him is one of blatant consideration; it makes Jon feel rather like a curiosity, not one of Elias’ colleagues. He has the intrusive thought that Elias _could_ just leave him here until he suffocates, trapped behind a window like a doll in a box — his own personal freak show.

 _Please,_ Jon mouths, because it seems like the only other thing he can do.

After several moments, Elias nods, a purposeful set to his jaw. He removes a dark-covered book from beneath his arm, then begins to slide the plexiglass away from the top of the bath.

Dizzily, Jon sits up; as long as he doesn’t breathe in, he can sit in the open air, muscles protesting at the sudden movement. He only deigns to lower his neck back into the water when dark spots begin playing across his vision. Even then, it’s only to inhale, and then he’s rejoicing in the freedom of movement once again, feeling the cool breeze on his damp skin.

“What—” Jon coughs, leaning back to submerge the gills while leaving his face out of the water. Even then, it’s a palpable effort to speak, as though his throat has restructured itself without consideration for his voice. It comes out raspy and strained. “What’s happening to me, Elias?”

“I’m not entirely sure.”

Elias sits down on the edge of the tub, the very picture of elegance. It must be someone’s fantasy to have a well-dressed man looking at them like that as they lie in the bath, but not Jon’s.

“Your best guess, then.”

“Of course.” As Elias speaks, he idly begins to trace circles in the bathwater. Jon shivers at the way it makes the currents shift after so long in stillness. “I would wager that some supernatural entity has latched onto you, rather like a parasite, and is attempting to subvert you for its needs.”

Jon feels a shiver run down his spine, quite unrelated to the coldness of the water. Elias pauses, looking at Jon with an expectant expression.

“What—” Jon winces, each word hurting more and more. “What needs?”

“I’d be hard-pressed to speculate right now, but— to turn you into something designed to spread fear, perhaps even violence.” Jon sucks in a shaky breath through his mouth, just to ground himself on his aching lungs. Elias continues, seemingly oblivious. “I doubt it’s personal, for what it’s worth. Most likely, you were simply the most susceptible candidate in the Institute.”

Elias mutters something derisive; Jon makes out the words ‘temple of the Eye’, but they don’t exactly fill him with confidence. Jon finds himself beginning to laugh, but, just as quickly, he starts to cough. It’s like he’s being punished for every human sound he makes. 

He’s stirred from hysteria by Elias’ hand on his shoulder, warm and solid as it presses into the soaked fabric of Jon’s shirt. The cold isn’t bothering him as much as it should be. It feels natural.

“So what now?” Jon manages.

“I have a suitable pool at my home if you’re amenable to staying there— unless you’d prefer to live in my office bathtub until we manage to resolve this situation?”

A pool doesn’t sound like a healthy environment — his eyes feel the phantom sting of chlorine just at the thought of it — and Jon is hardly the strongest swimmer, but anything would be better than being trapped here. At least in a pool he could move around, lose himself in the shifting currents. 

Jon tries to summon his voice, but even the idea hurts his throat, so he just waves at the gills; he can’t exactly go anywhere when he starts suffocating as soon as he’s out of water.

Elias’ laugh is warm and resonant as he reaches for the book he’d brought in with him. 

Oh. Of course. It’s a Leitner. Because Jon’s day wasn’t bad enough already.

“We’ve had possession of this since James Wright’s time,” Elias offers, in the same patient explanatory tone he always has when imparting information on the supernatural. “It’s a variation on a book about conducting autopsies. It’s, ah, rather unsubtle when read to excess, but you’ll be able to temporarily suspend your breathing with the passage I’ve marked.”

Jon swallows. His hands are wet, skin wrinkled with moisture, and they are shaking in fear. Still, he takes the book when Elias offers it to him, flipping through the dusty pages and doing his best not to take in any of the words. The passage Elias has marked — with a post-it note, of all things — is blessedly short. Jon slams the book shut as soon as he finishes reading.

“Excellent,” Elias murmurs, pulling the book from Jon’s hands.

Everything has suddenly gone very hazy. He’d compare it to a bout of dissociation, everything turned distant and immaterial. He sits up slowly, every movement feeling pointless. His chest neither rises nor falls. He makes no effort to breathe in or out.

“I see what you mean about subtlety,” he says, though his tongue is cold and sluggish in his mouth. He feels like a dead man who hasn’t quite got the idea yet.

“Quite,” Elias replies, amusement tempered by something sharp and watchful.

Jon can hardly summon the impetus to move; Elias has to guide him upwards most of the way. His clothes are damp and cling to his skin, and it would be easy to give into how they weigh him down. He could just lie there and wait for nothingness to claim him.

Elias’ touch is feather-light as he eases Jon out of the bath and onto the tiled floor.

Neither of them speak as they walk out to Elias’ car. Intellectually, Jon knows he had questions — he remembers the pace at which they’d run through his mind. But they’ve been swallowed by a quiet voice whispering the only truth that matters: he’ll be dead eventually. All life leads to death.

London traffic is as arduous as always, and even Elias looks ruffled by the time they stop outside a townhouse in the richest part of Kensington. Jon looks at him, blinking slowly at the glimpses he catches of the man behind the bureaucrat. 

Elias runs a hand through his hair. The moment breaks.

The journey into the house is largely a blur — it all seems to be decorated in the characteristic minimalism of those with too much money and too little sense. Even disconnected as he is, Jon doesn’t think much of it. It’s only when they enter the library that something stirs in Jon’s thoughts. 

It’s absolutely gorgeous, more books than he can easily comprehend. It’s bigger than the Institute library, and tells far more stories — curios sit on many of the shelves, little things that Jon knows, somehow, are artifacts in their own right. The covers are a mixture of old and new, but they all promise knowledge, and that breaks Jon from his reverie.

“You like it?” Elias sounds pleased, his smile shaded with amusement.

Jon nods slowly, resisting the urge to reach out damp fingers to Elias’ collection.

“We don’t have time for you to browse, I’m afraid. The effects of the book are only temporary.” Elias’ voice is gentle as steel, and his touch is just as firm.

One wall had seemed empty, but now that Elias turns him to look, Jon realises it’s a large glass tank. It reminds him of a fish tank, the floor covered in rocks and plants and the kind of decorative furniture that no fish could ever use. He knows he should care why Elias has this, but there’s just a dull relief. He feels dead, but he knows he’ll lapse back into life soon, and suffocation would be an unpleasant way to meet a more permanent end.

He doesn’t need to be told to climb the twisting stairs that lead to the top of the tank.

Elias stops him before he can succumb to the water’s embrace.

“It won’t be easy to swim in what you’re wearing,” Elias murmurs, already beginning to unbutton Jon’s vest. The sodden fabric falls to the floor with a wet thump, and Elias’ fingers brush over Jon’s shirt, a silent question in his eyes.

Jon considers it. It seems almost too intimate — but then, Elias has seen him choking, seen the lines that now mar the skin of his neck. Professionalism goes out of the window in these situations; Sasha has told him several similar horror stories from her time in Artifact Storage.

“Not my trousers,” he manages to say, and Elias looks scandalised by the very suggestion.

“Of course not. They’re lightweight enough that you’ll be fine for now.”

Jon sags in relief. If his heart wasn’t currently still and lifeless in his chest, he would blush as Elias maneuvers his shirt from his shoulders. That, too, falls to the floor. Sitting down at the edge of the tank, Jon slips his shoes and socks off, neatly piling them by the mess of fabric.

Slowly, Jon lets himself slide into the water.

At first, he sinks like a stone, but as he relaxes, feeling life tingling in his fingertips again, he rises to the surface to stare up at Elias. He can’t summon any words, but he hopes the tilt of his head is enough to convey his curiosity about what Elias has planned to fix this.

Elias is crouched down to look at him, and the smile on his face is prideful, almost possessive.

“You’re going to be _fine,_ Jon,” he says, like it’s a promise— like it’s a threat.

**Notes for the Chapter:**

> chapter-specific warnings: suffocation; extended confinement in a very small space; brief ideation of self-harm; supernaturally-induced dissociation; supernaturally-induced musings on death


	2. appetite

**Notes for the Chapter:**

> chapter-specific warnings in chapter end notes

The appetite comes next. 

It’s gradual, starting as an ache in Jon’s jaw. Over a few hours, his teeth grow tender and his gums turn raw. He has to wonder what being underwater for so long is doing to the state of his mouth.

Every day, morning and evening, Elias comes downstairs and feels him the soulless meal of a commuting businessman — bland sandwich, crisp bites of fruit, and a bottle of clean water. Much to Jon’s resentment, Elias hand-feeds him most of it.

“You’re hardly the most athletic,” Elias had said when Jon had protested. “Better that you use your arms to keep yourself afloat, hm? It’s never harmful to build some upper body strength.”

So Jon submits to the indignity of eating from Elias’ hand; it isn’t as though he has a better option. 

There’s no clock to mark the time, but Jon would guess that Elias spends about an hour with him each night. Once he’s finished helping Jon eat, he sits down in his armchair and tells Jon about the goings-on at the Institute.

“Sasha has just taken over as the Head Archivist,” Elias explains, leaning forward so Jon can see the dark gleam of his eyes. “She asked after you as one of her assistants; I informed her that you’re indefinitely indisposed for medical reasons, and that you’d appreciate your privacy.”

Jon swallows, feeling a strange mixture of relief and— betrayal?

He doesn’t want anyone seeing him like this. He only tolerates the humiliation of it now because he knows —  _ hopes _ — that Elias is researching a way to fix this, and because it isn’t as though he has any other options. At least here he has food, and space to move, and occasional company.

The only real downside, ignoring his irrational unease about the whole thing, is how goddamned bored he is. There’s just nothing to do, no way to entertain himself except swimming in circles.

“I could work from here,” he suggests, feeling foolish as soon as it passes his lips.

Elias gives him a chiding look, and he flushes.

“With your voice in the state it’s in? Hardly useful for follow-up calls. Besides, I sympathise, but I’m not bringing electronics near an open pool of water. Electrocution is as undesirable as suffocation, when it comes to your situation.”

Jon massages his jaw, not making any effort to hide his scowl.

“Don’t you think I can be trusted with my own safety?”

“Of course you can,” Elias soothes, his smile rather like one you’d give a precocious child, or a pet. “But accidents happen, you know that.”

With that proclamation, Elias stands up, promising to check in before he goes to sleep. It’s a clear end to that line of conversation — subtext so open that even Jon can pick up on it without a fuss.

As several days pass, tracked only in Elias’ comings and goings, the meals get more and more unappetising. Despite his hunger eating away at his stomach, it’s becoming an effort to force himself through a single bite of the sandwiches Elias brings him.

It doesn’t help that Jon’s mouth is beginning to hurt more and more. He can connect the dots between two occurrences; pain led to the gills lining his neck, and now he’s in pain again, it’s just a matter of time before something new and horrifying happens to his body.

One evening, his appetite is nonexistent.

Even when he forces himself through it, the bread only makes him feel sick; he spends half an hour with his head curled over the edge of the tank, pain and nausea warring in his stomach.

The whole time, Elias kneels beside him. His expression is impassive, not even softening when Jon manages to meet his eyes. The movement of his hand in Jon’s hair is perfunctory, echoing the idea of comfort — evenings spent with his head in Georgie’s lap — but not bringing any solace in its own right. It’s hollow, but Jon feels pathetically grateful for it anyway. It’s all he has.

When he finally feels like he can breathe again, Jon looks up at Elias.

“Give me something worth eating.” His voice is barely more than a whisper at this point, and every word tears out of his throat like sandpaper. He tastes blood as he swallows. “Please, Elias.”

Elias raises both of his brows, his lips pursing.

“Is this not to your tastes? I’m afraid I’m too busy to cook for you myself.”

“It’s…” Jon has to duck below the water for a moment, soothing his voice with the cool flow of water filtering into his neck. “It’s nothing, Elias. I don’t— I’m not getting anything from it.”

“I’ve already made a lot of effort to accomodate your needs, Jon.” There’s an anger in Elias’ voice that Jon has never heard before, barely restrained under a mask of placid intellectualism. “You’ll forgive me if it isn’t a five star experience.”

“I—” 

Jon is caught between apologising and sticking to his argument. Perhaps he shouldn’t have stirred up trouble, because now Elias is looking at him like he’s worth nothing. After a long, tense moment, Elias picks up the remaining half of the sandwich. The bread is stale, unyielding beneath his fingers, but his expression is expectant as he holds it to Jon’s mouth.

“Finish your dinner, Jon.”

The bread is tasteless and disintegrates between his teeth; the fillings have gone cold and limp. His stomach feels no less empty when he finishes, but it’s better than Elias taking it and leaving.

It’s like Jon’s anger triggers something, because that night, he can’t sleep for the pain in his gums.

One by one, Jon spits out blunt human teeth, and one by one, they regrow sharp. 

He cuts his tongue open as he probes through his mouth. The metallic taste of his blood makes him ache for something that will satisfy his hunger, something he can rip and tear that will fill the hollowness of his stomach.

Elias makes no comment on the pile of bloodied teeth at the edge of the tank that morning, just raising an eyebrow with a smile. All of yesterday’s scorn seems to have vanished, replaced by quiet amusement. He passes a few minutes of small talk and, much to Jon’s resignation, the status quo seems to have resumed.

Then Elias leaves without feeding him, and Jon feels his empty stomach sink.

He does his best to follow Elias down the spiral staircase, though he still hasn’t got the hang of maneuvering himself in the water. Elias doesn’t even look at him, not even when he slams a fist against the glass and the reverberations knock him off-kilter.

“Elias,” he tries to say, but even if his voice were at its best, it all comes out as bubbles.

Elias leaves without glancing back.

Jon’s terror mingles with a vicious fury. He’s all the more aware of the sharpness of his new teeth, and he has the intrusive thought of filing his nails to match using the rocks on the floor of the tank. He’s almost bored enough to give the idea genuine consideration.

With nothing better to do, he still finds himself piling the rocks into stacks that could almost be called artistic, occasionally peering out at the closest shelves in a vain attempt to read any of their spines. It’s not a thrilling way to pass a day, but he’s almost getting used to it.

All the while, his anger burns in his aching stomach.

When Elias returns, food in hand, Jon bares his teeth at him instinctually, making sure that Elias can see every gleaming point of those fangs. If Elias won’t listen to his words, maybe he’ll listen to his teeth instead.

Elias just shakes his head, his smile tight with exasperation.

“Really, Jon. This is just petulant.”

He kneels down in the usual spot, gesturing for Jon to approach him.

Jon swims forward, briefly distracted from his ire by his own clumsy movements, and Elias’ expression softens slightly. He reaches into the bag by his side, and Jon hears his own stomach growl.

“Good boy,” he murmurs, so low that Jon is sure he wasn’t meant to hear it.

Jon’s brief flutter of embarrassment fades back into anger as Elias pulls yet another sandwich from the bag, followed by some equally unappetising slices of apple. Before he can kick himself backwards, Elias reaches forward and gently cups the back of his neck, holding him in place.

“You must be hungry.” It’s nothing more than a bland statement of flat, but it makes Jon scoff, glaring up at him. His teeth are bared again; he hadn’t even realised.

Sighing, Elias picks up a slice of apple, delicately holding it between two fingers. He pulls Jon closer, waiting for Jon to open his mouth wide enough that Jon can take it between his teeth.

Jon takes one bite of apple, then another, and then his teeth close on the skin of Elias’ finger.

He’s gratified to taste blood, to watch Elias flinch. For the briefest moment, the expression on Elias’ face is one of pained wonder. Then it shutters, cold and hard as stone. His brows narrow in anger, his lips thin in disdain. The hand at the back of Jon’s neck rises to tangle fingers in his hair.

“Well, I suppose I should have foreseen this.”

Elias’ fingers tighten in Jon’s hair until his eyes begin to water with pain. He tries to make some kind of sound, to plead or protest; there’s no trace of his voice left, just his gills fluttering in pure animal panic. Elias hums, tilting his head as he looks down at him.

“This power that’s transforming you preys on your thoughts as much as your body.” Elias pulls Jon’s head backwards. His neck burns with the strain of the position, but he isn’t strong enough to pull himself free. “These things are insidious, and I wouldn’t want you to lose yourself in the impulses that it pushes on you.”

Licking the blood from his finger, Elias uses his free hand to lift Jon from the water, just enough that his gills are left fluttering breathlessly. Tears run down his cheeks, and Elias watches, impassive.

“Obviously I can’t blame you for your lacking self-possession, but I need you to focus on controlling yourself from now on, Jon. Can you do that for me?”

Dark spots dance across Jon’s vision. He wants desperately to nod, to say yes, just so Elias will let him go again, but all of that power has been taken from him.

Still, Elias seems to understand, dropping him into the water without warning.

Dizziness makes it hard for Jon to regain his coordination. He manages to swim backwards, pressing himself against the back wall of the tank. There’s nothing for him to grip onto; his oxygen-starved muscles ache with the effort of keeping him afloat. 

He watches as Elias pulls a pack of plasters out of his bag. Elias looks back, not breaking eye contact as he tends to the wounds Jon left, and a realisation comes over Jon like a tsunami: Elias knew that this would happen. He planned for it.

It makes the next words sit all the heavier on Jon’s shoulders:

“I’ll order some gloves, but you’ll have to do without food until they arrive. I’m sure you’ll be fine.”

Elias smiles then, and all those blunt white teeth look sharper than any of Jon’s new fangs.

**Notes for the Chapter:**

> chapter-specific warnings: confinement, understimulation, malnutrition, starvation as punishment, suffocation, biting, elias-typical manipulation
> 
> i hope you enjoyed it!


	3. lights

**Notes for the Chapter:**

> chapter-specific warnings in chapter end notes

The night after he tastes Elias’ blood, Jon’s skin starts to itch. 

It’s hardly the only thing disturbing his rest — his hunger mingles with his anger at Elias, and the resulting viciousness heightens his unease at how much he’s changing. Maybe Elias is right, and this is all for his own good, the only way to stop Jon from becoming something unrecognisable.

At night, the darkness of the library is complete, so he has nothing to focus on. At least in the daylight, he could distract himself by peering out at the shelves, wishing desperately that Elias would give him something to read. Even when he manages to quiet his thoughts for long enough that he might sleep, Jon’s skin tingles, a buzzing pins-and-needles sensation. 

It isn’t anywhere in particular. His whole body feels like there’s something shifting under his skin. It doesn’t lessen when he scratches at it, nor when he presses himself to the rocks he’s grown accustomed to hiding in. It’s just a bone-deep ache, heralding another awful change.

When he wakes up, the library is still dark.

Even without the lights on, there should be some meagre daylight filtering through the windows near the ceiling. But there isn’t even a hint of illumination, just a pitch-blackness that feels like it might stretch on forever outside the boundaries of the tank.

He waits, wondering if perhaps he’s just woken up early. That wouldn’t be out of the realm of possibility, and maybe Elias has a schedule for when the library lights are turned on.

Hunger is insistently making itself known. Dizziness makes his thoughts fade out whenever he tries to move, nausea rising as the gentle currents of the water push him from side to side. Even in the darkness, bright colours dance like fireworks across his vision, which is at least interesting in a morbid sort of way. It’s like a long day at work, preoccupied with a case, except for how there’s nothing to occupy his mind but his own predicament.

Jon scratches absently at his skin, and carries on waiting.

Despite Elias’ dire promise of punishment, Jon still half-expects him to arrive, food in hand, as though nothing has changed. It’s hard to reconcile the Elias he’s looked up to for years with the man keeping him captive, locked away from anything and everything that might keep him sane.

Surely it’s all for a purpose. Surely it’s all necessary to keep Jon from falling further into whatever power is changing him. Surely it isn’t just Elias, keeping Jon prisoner and watching him suffer.

Surely.

Elias doesn’t arrive.

Jon is stuck alone in the dark water with his own itching skin.

It isn’t just his skin that feels strange, he realises, after god knows how long suspended in nothingness.His eyes itch as well. They feel almost sticky, like there’s a heaviness coating them from sclera to pupil. He presses his palms to his eyelids, and the pressure only makes his eyes sting. They leak a warmth that might be tears or might be blood; he’s almost thankful that the darkness obscures it.

Slowly, his eyesight adjusts. 

He has no way to mark the time aside from the hunger pangs in his stomach, but eventually he can make out the vague shapes of the shelves.

In hopes that the noise will attract Elias to see what’s happening, Jon starts picking up pebbles, throwing them at the wall of the tank. There’s something satisfying in waiting for the impact, watching the dark shape hit an invisible barrier and fall to the ground. The sound resonates in the glass, and it’s almost enough to make him smile.

This is what Elias has reduced him to, apparently: childish games.

On one of his throws, something looks different. 

He throws again, and he catches a glimpse of light beyond the glass, tiny flickers of bright green appearing and disappearing in a way that Jon can’t track. It reminds him of will-o’-wisps, trying to lure him out of the closest thing he has to a safe haven. 

Anchoring himself on the greenery below, he swims closer to the wall of the tank. The flashes of light get easier to see, as though they’re approaching him in turn.

He peers through the glass, and all he sees is his reflection, gaunt and horrified — and then he notices the poisonous light emanating from him, luminescent freckles cresting in a wave across each of his cheekbones.

As Jon watches, more lights bloom dimly underneath his skin. 

The size is variable, he notes, nauseated curiosity building as he peers at himself. Some, like the glimmers of radiance on the edges of his face, are barely more than pin-pricks — but there’s a patch flaring to life at the center of his sternum which is nearly the size of his fist.

Using one finger, he traces lines between the spots of light like an esoteric game of dot-to-dot. They form patterns, he realises — one path up the center of his torso that branches outwards like a stylised tree; a symmetrical set of angles on his neck, disrupted by the conflicting lines of his gills, which are similarly aglow; trails of light down his arms that finally fade out at his hands.

_ Blaschko’s lines, _ Jon remembers from an ill-advised Wikipedia dive several months ago; the lines of cell development in the skin, only visible when suffering from certain conditions. 

He laughs silently, scornfully, air bubbling from his mouth. He has a condition, that’s for sure.

After a while, once the panic has faded into a numb terror, the gentle pulsing light starts to be something close to a comfort. Jon can cope with the fact that he’s glowing. It’s almost beautiful, if he doesn’t think about the greater implications for his body.

Unfortunately, his skin doesn’t stop itching. The feeling intensifies in some places and lessens in others, but it doesn’t vanish. As he watches his own reflection, he finds himself absently scratching at the back of his hand, and by the time he’s dragged his attention away from himself, that patch of skin has turned flaky and uncomfortable.

He closes his eyes and tries to rest, hoping for morning’s light to come soon.

Maybe when that happens, Elias will have an explanation for him. Better still, an apology.

Morning’s light doesn’t come, of course.

Jon opens his eyes already chiding himself for his foolish hope — hope that he would sleep for long enough to reach morning, or perhaps hope that Elias would take pity on him.

That tingling feeling below his skin has only got worse. He shifts, trying to get his bearings, and the fabric of his trousers moving against his skin is the most painful thing he’s ever experienced. His slacks are hardly designed for prolonged exposure to water, but this has to be something else.

Hesitant, keeping one eye on the library outside, he begins to unbutton his trousers. Elias could appear at any time, but it’s a risk Jon is willing to take to be in a little less agony.

It only gets worse as he peels his slacks off, inch by inch. The fabric feels harsher than he remembers, uncomfortable even below his fingertips. He can taste the blood seeping into the water from the marks that the cloth is leaving on raw and changing skin.

God, he’s so hungry. Right now, he’d eat anything Elias gave him, and he might not even bite.

His underwear is another point of reluctance. Despite what people may think, he’s not a prudish man; it’s just that he’d rather not be naked in a glorified fish tank owned by his boss. But the change he’s going through doesn’t care about his modesty, and in the end, he discards his boxers too.

There’s patterns of light on the skin of his legs too, dimmer but more evenly dispersed. They do nothing but illuminate the dark patches of inflammation where blood still seeps out of exposed tissue.

Something glistens in those wounds — not the red of human flesh, but a colder shade that chills him to see. He peers at that tender skin, closer and closer, until he almost thinks he’s worked it out—

The lights flicker on.

Jon flinches full-body at the sudden brightness, everything around him painfully overexposed. On instinct, he dives for the meagre shelter of the rocks, trying to find some semblance of darkness.

“Jon?” he hears Elias call, worry in his voice.

The lights turn down until Jon can keep his eyes open without too much pain. 

He peers out of his shelter and into the library proper. Elias is standing in front of the tank, looking exactly as put-together as when Jon last saw him. When their eyes meet, he schools his expression into one of concern, but Jon is already ducking back into the rocks.

Elias sighs, tapping his knuckles against the glass. It’s the same sound as when Jon had thrown pebbles at the wall, but this time, it sets his teeth on edge.

“Jon, I’d appreciate it if you came out of there.”

Jon presses himself low to the ground, creeping into the greenery so he can watch Elias.

“If you don’t show yourself, I’ll have to drain the pool and fetch you myself. Believe me, neither of us wants that fuss.” The tired exasperation in Elias’ voice sounds closer to genuine than anything else he’s said in Jon’s recent memory — although Jon knows for a fact that they have different reasons for wanting to avoid that situation.

Carefully, anchoring himself on some giant kelp taller than he is, Jon pulls himself upwards so Elias can see him. All of him. Poisonous glow and tender skin and all. 

Jon aims for a defiant tilt to his chin, but he’s too light-headed to be properly acerbic.

Elias makes no attempt to hide the way he looks Jon over, smiling all the while. 

“Beautiful,” he says, and he seems to mean it. 

The natural response would be to flush, but instead, Jon feels himself glow all the more brightly. It illuminates the tank — hell, the entire damned library is lit in lambent green by his traitorous flesh.

Elias gestures for him to turn around. Jon does, though he hopes his glare — metaphorical, this time — conveys exactly how grudging his obedience is.

It’s almost the most infuriating part, that Elias gets to know more about Jon’s body than Jon does. It’s only logical, of course: Elias needs to work out how to fix this, so he needs to know everything. But he’s never shared any of that information with Jon, and he’s not likely to start now.

Jon stays still there for a while, long enough that his vision begins to blur and his grip on the plant keeping him anchored begins to slip. It’s only when Jon feels like he’s about to pass out entirely that Elias speaks again.

“Come upstairs, Jon. You must be very hungry by now.”

With a weak kick of his leg, Jon turns back around. He watches as Elias climbs that spiral staircase, watches as Elias stares down into the water with an expectant look on his face. 

“Bring your clothes up with you. I doubt you’ll be needing them anymore.”

It’s not the scolding Jon expected, and it sets him off-kilter enough that he just… does what Elias says. The fabric is heavy in his arms, but Elias is there to take it from him as soon as he surfaces.

“Good,” Elias damn-near purrs, and goddamnit, but his praise still sets butterflies off in Jon’s stomach, echoes of the junior researcher who wanted nothing more than to impress an intelligent authority figure.

Clothes deposited out of Jon’s reach, Elias kneels down by the water. He tuts as Jon swims backwards, lips pursing in frustration.

“Let me look at you, Jon. I can’t help if I can’t see what you’re dealing with.”

He holds out a hand. Jon reaches out in turn, watching as the dripping water makes a flicker of displeasure cross Elias’ face. That tiny spark of vindication fades as Elias takes his hand; the very feeling of warm, dry skin on his makes Jon’s eyes well up.

Elias doesn’t acknowledge the tears sliding down Jon’s cheeks. He just pulls Jon’s hand closer, his expression one of open curiosity. His touch circles the rough skin of Jon’s palm until Jon finally gives in and splays his fingers wide for Elias’ inspection.

The bottom of his hand is largely unchanged. There are a few faint lines of light that follow the major wrinkles in his skin — the sort of things that a palm-reader might use to tell his fortune. Otherwise, it’s the gentle calluses of academic life, and nothing else all that interesting.

When Elias turns his hand over to examine the back of it, that’s when Jon starts to feel sick. Where Jon had scratched at the skin, it’s become this horrible blue-green, like a bruise staining his flesh. It glitters, and he has to avert his gaze. It looks unhealthy, damn-near infected.

Elias clicks his tongue. He runs his fingers over the throbbing wound; Jon inhales through his teeth, a breath of poisonous air that does nothing to ease the pain.

“Don’t look away, Jon. It’s rather fascinating.”

Jon takes in a deep breath, gills flaring open.

It’s fine. It’s not his hand. It’s nothing to do with him. It’s just something that Elias is showing him. A fascinating supernatural anecdote shared between two colleagues. That’s all it is.

It’s a wound on someone’s skin, scratched open until the mundane gave way to something growing underneath. Elias graciously allows Jon to look closer, and he realises that the blue-green colour isn’t blood, or infection, but  _ scales. _ Tens of hundreds of opalescent scales, revealed from underneath human skin like butterfly wings from a chrysalis.

When he looks at it that way, it isn’t quite so bad.

“It’s progressing quicker than I’d expected,” Elias murmurs, shocking Jon out of the headspace.

Jon raises his eyebrows, wondering exactly how much Elias knows about what’s happening. As Jon is coming to expect, Elias ignores all his non-verbal signals, reaching into the bag he brought with him.

First, Elias retrieves a pair of thick gloves, so thick that Jon couldn’t bite through them even if he wanted to. He’s almost certain he doesn’t want to.

Jon remembers Elias’ promise and swims a little closer. He’ll take the blandest of Waitrose sandwiches that Elias has to offer him; he just needs to eat  _ something. _

What Elias pulls out instead is a tub of neatly sliced fresh fish.

Jon’s mouth waters. It’s exactly what he didn’t know he wanted. He very nearly bites his own lip open with how hungry he feels. The fish will satisfy him, he’s certain.

One by one, Elias feeds him pieces of fish. It might even be too much, after the malnutrition of the last few— days? weeks? But the taste, the texture — all of it is perfect. He doesn’t stop until he’s exhausted everything Elias has brought with him.

It’s only then that he swims backwards, watching Elias as warily as Elias seems to be watching him.

Jon wants to ask what Elias wants from him; why he’s keeping Jon here; why he isn’t helping. But his voice has long-since deserted him. He mouths the words helplessly, and Elias raises an eyebrow.

“Speak up, Jonathan. I’m afraid I don’t catch your meaning.”

Jon’s cheeks burn in wordless humiliation, and his skin casts the world in shades of acid and poison. Those envious greens suit Elias perfectly.

**Notes for the Chapter:**

> chapter-specific warnings: sleep deprivation, self-harm (picking/scratching skin), extended period in darkness, starvation, isolation, elias being a manipulative prick, threats of suffocation, humiliation for being unable to speak
> 
> if i don't get the next chapter done by the end of tomorrow (or technically today _glances guiltily at it being quarter past midnight_ ) then it might be a few extra days while i concentrate on uni work. but i am very excited for the next chapter.


	4. locomotion

**Notes for the Chapter:**

> i return! after nearly two months of no updates and one month of just plain writer's block. this chapter gave me such troubles but i am satisfied with it now!
> 
> extra warnings for body horror on this one

Elias has taken to reading by the tank, these days.

Sometimes he sits in front of the glass, as though to use Jon’s glow as illumination in the dim light, but more often than not, he opts for an armchair near the edge of the water. He always angles himself away so Jon can’t read alongside him. 

Jon is running out of reasons to justify it; he wants so badly to pretend Elias is anything other than actively malicious. He clings to the vague concept of a happy ending like an anchor — like a weight dragging him to the depths.

One day, when Elias finishes reading, he leaves his book on the table.

That startles Jon in itself; Elias never leaves books unattended where Jon might be able to reach them. At first he’d assumed it was to protect the paper from water damage, but he knows better now.

When he realises what book it is, there’s a treacherous flicker of hope in his heart.

It’s hard to tell for certain from this distance, of course. Jon’s eyesight has adjusted to the water, and his vision in the open air has deteriorated accordingly. But the dark leather of the cover is achingly familiar; it looks an awful lot like the Leitner that Elias had used to bring him here.

The idea of using a Leitner as an escape plan fills Jon with dread, but no more than the idea of being trapped here for the rest of his life. What other option does he have? 

Jon inhales deeply, his gills fluttering against the skin of his neck. Before he can change his mind, he pulls himself out of the water with both arms, sending himself tumbling across the floorboards. His nails catch in the grain of the wood as he steadies himself.

It’s surprisingly little effort to push himself up on his arms. His legs, though— they ache. When he tries to get leverage, they slip out underneath him; he ends up flat on his back, winded and in pain.

His lungs are already burning. He has to do this quickly.

Jon tries once more to stand, but his ankles don’t bend the way he expects them to. The range of motion is all wrong, like he’s been underwater for so long that his body doesn’t know any position that isn’t the pointed-toe stance of a swimmer. His toes curl against the wood beneath him; he refuses to acknowledge how wrong the sensation feels— refuses to look down at himself at all.

With no other options, Jon starts to drag himself across the floor towards the table. It’s not a dignified affair; rather like how seals are graceful creatures, but only when they’re in water.

As if from very far away, the door to the library creaks open. 

Jon freezes, tracking Elias’ footsteps. They’re painfully loud in the open air, unmuffled by the water. He’s halfway to covering his ears with his hands before he manages to refocus on his goal.

Maybe if he’s quiet, he won’t attract Elias’ attention. But then, if he’s quick, he might be able to read the book before Elias is any the wiser. He could dive back into the water afterwards — but the splash might raise Elias’ suspicions. 

(It’s futile. He knows it’s futile. But he has to try.)

With every inch Jon manages to drag himself, legs scraping agonisingly across the floor, Elias’ footsteps get closer and closer. Across the floor, up the stairs— and there he is, pristine as always.

Elias’ eyes are as grey as storm-clouds. When Jon meets his gaze, there’s a lightning-flash certainty that Elias  _ knows _ — that somehow, he saw everything from the moment he left the room and Jon made his plan to escape. His eyes rake over Jon, his brow furrowing in disapproval.

“Oh, Jon. You’re really quite ungrateful, aren’t you?”

Jon tries desperately to push himself away, fingers scrabbling at the floor beneath him, but Elias crosses the room in a few easy strides. He crouches over Jon, hands coming down to hold his wrists in place while he half-sobs, half-suffocates.

“All of the hospitality I’ve shown you wasn’t enough. You’d rather end up captured for study than spend a single second longer here. I’ve given you all I can afford to, you know that.”

Desperate for any kind of leverage, Jon tries to kick out. His legs twitch uselessly against the floor.

Elias’ expression softens into something pitying — the kind of sympathy you might feel for a pet who doesn’t understand some simple principle of how the world works. His thumbs brush across Jon’s skin in a parody of comfort, all the more hollow given that his grip on Jon doesn’t relent.

“I know it’s hard to accept, but you just aren’t fit for the outside world anymore.”

After a breathless eternity, Elias stands up. He sighs, his disappointment clear, then nudges Jon back into the tank with the tip of one well-polished shoe. 

Jon lets himself sink, lost in the relief of cool water filtering through his gills. By the time he’s calm enough to resurface, Elias is gone, taking all hope of escape with him.

The worst part is that he was right: whatever Jon is becoming, it’s not something adapted to life out of water. Jon can’t ignore that anymore. He has to confront what’s happening to him. 

Nausea rising in his throat, he presses the pads of his fingertips to his thighs. 

The scales that cover his skin are shining-smooth, and unlike his upper body, there are no gaps for the softness of flesh. As his hands crest down below his ankles, another tide of sickness sweeps through him, so visceral that he worries that he may actually throw up.

Fins would be the word, some detached part of his mind informs him.

Long and flowing and probably rather beautiful. Utterly inhuman. 

He pulls his hands away before his curiosity gets the better of him. He doesn’t acknowledge how webbing is creeping up the gaps between his fingers — how every part of him is adapting, in a way.

Over the next few days, the change becomes painful. 

It’s as though Jon’s acknowledgement of what’s happening has alerted his body to the fact he should be able to feel it. A dull ache sweeps from hips to toes, like everything below his skin is shifting.

That doesn’t seem far from the truth, if he’s honest with himself. As hours go by, it gets more and more difficult to pull his legs away from each other. His conclusion is that his pelvis is reshaping itself — which would explain the pain — and his range of movement is suffering as a result.

As Jon’s discomfort increases, Elias’ behaviour turns strangely kind. It’s suspicious, obviously, but there’s only so long Jon can hold out against comfort when everything below his waist is in agony. 

Elias feeds him morsels of seasoned fish from between bare fingers, and Jon is far too tired to bite; he can’t take more pain, not now. After the meal, Elias’ hand comes up to cradle Jon’s head, fingers nestling in his hair. The touch makes Jon want to weep, and he can’t even place  _ why. _

“If you’re amenable,” Elias murmurs, so soft, so careful, “I can read to you, for a while.”

Tears well up in Jon’s eyes. All he can do is nod, and let Elias guide Jon’s head into his lap. 

As Elias’ fingers card through Jon’s hair, a haze begins to cover Jon’s thoughts. It’s a pleasant detachment, warm and sweet, where all he has to think about is the low tone of Elias’ voice. The words fade out into simple noise, the pain fades into numbness, and slowly, Jon drifts to sleep.

When he wakes up, his ankles have fused together. Everything below his waist is unified, legs blended together in a monstrous parody of a storybook mermaid’s tail.

Elias is nowhere in sight.

Jon expects anger, or panic, or grief, but each of his thoughts seems to drop like a stone into an abyss. The water around him dulls every sensation. He floats there, cradled in warmth, and he feels nothing at all.

It’s not the end, of course. But after a while, he stops keeping track of how much longer his tail grows. It’s not really his, after all.

**Author's Note:**

> thank you for reading! i hope you enjoyed! 🤞 that i get the rest of this fic done, but in the meantime, go and read the rest of the series! it's all written by very skilled people!


End file.
